I'm trying to get my Chaos Pendulum scene to work, but it ain't happening. I
can't get the math right!

Apparently, both gravity and magnetism work using the "inverse square law of
attraction". I don't actually *know* what that means, but I've given it my
best guess...

Forget gravity, let's talk magnetism. Suppose I have a magnetic ball at
point P, and a magnet of strength S located at point Q (and fixed in place).
Now, I recon the force experienced by the ball is in the direction Q - P,
and it's strength is equal to the reciprocol of the square of the distance
from P to Q; i.e., force = S / vlength(P - Q) * vlength(P - Q).

But hang on... wouldn't that mean that the way the force drops off as we
move away from Q is dependent on our units of measurement? Suppose P is 1
meter from Q. Then we have S / 1 * 1 = S. But if we write this as 100
centimeters instead, we have S / 100 * 100 = S / 10000. Um... a little
confused here!

Wouldn't that also mean that if P = Q, then the force of the magnet is
infinite? (Or more importantly, if P *almost* equals Q, the force would be
astronomically large.) Now I'm *really* confused!

By the way... is the force excerted by a *real* magnet dependent on the mass
of the magnetic ball?

OK, my head *really* hurts now...

Help!
Andrew.

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